Motor support for ventilating fans



J1me 1932- c. E. JOHNSON MOTOR SUPPORT FOR VENTILATING FANS Filed Jan.-13, 1951 w MW 3 4 ATTaQ/VE 4 Patented June 14, 1932 more!) STATES PATENTOFFICE CARL E. JOHNSON, OF PASADENA, CALIFORNIA MOTOR SUPPORT FORVENTILATING FANS Application filed January 13, 1931. Serial No. 508,481.7

\ mission of vibrations from the motorto the fan. These transmittedvibrations cause noises which are conveyed through the ventilating pipeassociated with the fan. Such a practice, therefore, of connecting amotor to a ventilating fan is very objectionable in theatres and hallswhere absolute quiet is necessary.

It is an object of my invention to eliminate this objectionable featureresulting from the present practice of attaching the motor directly tothe fan by providing a structure for accomplishing this attachment whichwill absorb or damp out the vibrations of the motor so that they are nottransmitted to the fan.

To accomplish this purpose I provide a resilient means adapted to beinterposed in the connection between the motor and the fan. With such aconstruction it is desirable that the motor should be adapted to beeasily, quickly and adjustably attached through-the resilient means tothe fan.

It is a corresponding purpose of my invention to provide a constructionfor attaching a motor to aian which permits the motor to be easily andquickly attached to the fan through a resilient means and in such amanner that this attachment is adjustable. I It is a further object ofmy invention to provide such a construction of a sufiiciently rigidnature to require little or no attention or repairs.

It is still another object of my invention to provide a construction ofthe class described in which the parts most apt to be worn may be easilyreplaced and cheaply manufactured.

To illustrate my means of accomplishing the foregoing ob ects, andothers, some of which will be made evident hereinafter, I will describea preferred and alternative form of embodiment of my invention, theseembodiments being illustrated in the drawing.

In the drawing, which is for illustrative purposes only,

Fig. 1 is a partially sectioned view of the 5.1 motor support of myinvention.

Fig. 2 is a view taken as indicated by the line 22 of Fig. 1.

Fig. 3 is a fragmentary view of an alternative form of my invention. co

Referring to the drawing, and particularly to Fig. 1, the numeral 11indicates an electric motor which includes a stator 12 and a rotor13.The motor 11 may be of conventional induction type, but is preferably 05of the variable-speed type, such as those motors having wound rotors ordual-wound stators. The rotor 13 is non-rotatably secured to a shaft 14,which is mounted in bearings 15. The bearings 15 are disposed in bearingrecesses 16 formed by an inwardly extending annular flange 17 on each oftwo endbells 18. Each of the end-bells 18 is provided with acylindrical, inwardly extending side wall 19, on the inner surface ofwhich is formed an inwardly extending annular shoulder 20. Asillustrated in Fig 1, the annular shoulders 20 are adapted to cooperateto engage between them the sides of the stator 12. Each of the sidewalls 19 is 30 provided with an opening 21 therethrough parallel to theaxis of the rotor 13 and for a purpose which will be later described.

The shaft 14 extends through a central 0 lindrical opening 22 formed inone of th 'e end-bells 18 and is non-rotatably secured as by a key 23 toa rotor 24 of a fan 25. Attached to the rotor 24 of the fan 25 is aseries of blades 26 adapted to be rotated by the shaft 14 within acylindrical casing 27.

- The ventilating fan 25 may be of the blower or exhaust type, the formherein illustrated including an inlet opening '28 in the side of thecasing 27 and an outlet opening (not shown) in the periphery of thecasing 27 The supporting structure of my invention indicated by thenumeral 29 includes a ring v30 having openings 31 therein adapted tocoincide with the openings 21 of the end-bells 18. The ring 30 is of awidth substantially equal to the width of an annular flange 32 formed onthe outer surface of each of the end-bells 18 so that the ring 30 may bepositioned upon and secured to the flange 32. The ring 30 is providedwith a plurality of radial arms 33, here shown as three in number, eachof which is provided at its outer end with a hub portion 34 having acylindrical opening therethrough parallel to the axis of the ring 30. Asillustrated in Figs. 1 and 2, each of the arms 33 may be provided with aweb 35 extending down its middle to provide additional strength.

Each of the hub portions 34 is adapted to receive a lining 36 ofresilient material such as rubber, which extends throughout the lengthof the hub portion 34. The lining 36 provides a central cylindricalopening 37 adapted to receive a bolt 38.

The supporting structure of my invention includes also two end-plates 39of a diameter slightly larger than the diameter of the hub portion 34.One of the end plates 39 is provided with a central cylindrical opening40 having a diameter substantially equal to the external diameter of thelining 36. The other of the end plates 39 has a central cylindricalopening 40a of a diameter substantially equal to the diameter of theopening 37. Adapted to be positioned upon the bolt 38 adjacent each ofthe end plates 39 is a cylindrical pad 41 of resilient material such asrubber. Each of the pads 41 has an external diameter substantially equalto the external diameter of the end plates 39 and is provided with acentral cylindrical bore 42 adapted to receive the bolt 38. The pads 41abut against the end plates 39 and the ends of the lining 36.

As best illustrated in Fig. 1, one end of the bolt 38 is adapted to bethreadedly received in a ring 43 which bears against the inner surfaceof the end of the casing 27. One of the pads 41 of resilient material isplaced upon the bolt 38 adjacent the outer surface of the end of thecasing 27 and that one of the end plates 39 having the larger centralopening 40 is placed against this resilient pad 41. The lining 36 beingassembled as indicated in Fig. 1 inside the hub portion 34 and aroundthe bolt 38, the other one of the end plates 39 is placed adjacent thehub portion 34, and a second resilient pad 41 is positioned upon thebolt 38 so that it contacts that end plate 39. A second plate 44 is thenpositioned upon the bolt 38 so that it engages the other surface of theresilient pad 41. This entire assembly is held in proper position uponthe'bolt 38 by a nut 45 screwed upon the end of the bolt 38 until theproper degree of compression of the pads 41 has been achieved.

The ring 30 is attached to the end-bells 18 by bolts 46 which passthrough the openings 21 of the end-bells 18. As indicated in Fig.

1, the bolts 46 pass through the end-bells 18 after the end-bells havebeen positioned one on either side of the stator 12 so that when thebolts 46 are projected through the openings 31 in the ring 30 andsecured in place by nuts 47 and lock washers 48, the end-bells 18cooperate to lock the stator 12 in its proper position.

It should be noted that the bolts 46 operate to secure the end-bells 18,the stator 12, and the ring 30 all in their proper positions relative toeach other. It should also be noted that only three bolts 38 arerequired to attach the arms 33 to the fan casing 27. It should beapparent that with such a construction the motor 11 may be adj ustablyattached to the fan 25 so that the fan rotor 24 rotates in its properrelation to the fan casing 27. It should likewise be apparent that, bymeans of the three bolts 38 and the three nuts 45, the resilient pads 41may be compressed to any extent desired so that the correct degree ofresilient effect may be secured in the attachment between the motor 11and the fan 25.

In Fig. 3 there is illustrated an alternative form of my invention whichdiffers from the preferred form already described in that no ring 30 isrequired. Instead, each of the arms 33 is provided at its inner end witha hub portion 49 having an opening 50 adapted to permit the extension ofone of the bolts 46 therethrough. Such an embodiment of my invention hasthe advantage of being somewhat cheaper in its manufacture than thepreferred embodiment herein'before described.

In both embodiments of my invention the resilient pads 41 operate toabsorb or damp out vibrations between the motor 11 and the fan 25 in thedirection of the axis of the bolts 38. The resilient lining 36 operatesto absorb or damp out vibrations perpendicular to this axis so thatvibrations in whatever direction they may occur are diminished oreliminated between the motor 11 and the fan 25, and thus not transmittedto the fan 25. Such a construction, therefore, prevents the transmissionthrough the ventilating pipes of those audible noises caused by the vi-W brations of the motor which have been proven objectionable in thepresent practice of attaching the motor to the fan. It is a feature ofthe invention that the resilient means 1 rotor 24 and the casing 27should excessive vibration of the motor occur.

Inasmuch as the only parts of the supporting construction of myinvention apt to be worn or to require replacement are the resilientpads 41 and the resilient linings 36, and inasmuch as these may bereplaced simply by the removal of the three bolts 38, it should beapparent that I have by my invention provided a supporting structure inwhich the re lacement of the parts may be accompllshed by theexpenditure of very little time and effort.

Although the embodiments of my invention hereinbefore illustrated anddescribed are fully capable of performing those objects primarilystated, my invention may be embodied in various other forms, andconsequently I do not wish to be restricted to those embodimentshereinbefore set forth.

I claim as my invention:

In a support construction for a motor driven fan, the combination of: aring adapted to be attached to the casing of said motor; arms on saidring, each of said arms having an opening at its end; a resilient liningin each of said openings; a resilient pad on one side of each of saidarms; and bolts adapted to extend through said openings and engagingsaid linings to adjustably secure a fan against said resilient pads.

In testimony whereof, I have hereunto set my hand at Los Angeles,California, this 8 day of J an., 1931.

CARL E. JOHNSON.

